1. Take your stance, feet a little closer than you think it needs to be and with your toes out more than you like. Your shins should be about one inch from the bar, no more. This places the bar over the mid-foot ! the whole foot, not the mid-instep.

2. Take your grip on the bar, leaving your hips up. DO NOT MOVE THE BAR.

3. Drop your knees forward and out until your shins touch the bar. DO NOT MOVE THE BAR.

4. Hard part: squeeze your chest up as hard as you can. DO NOT MOVE THE BAR. This establishes a "wave" of extension that goes all the way down to the lumbar, and sets the back angle from the top down. DO NOT LOWER YOUR HIPS ! LIFT THE CHEST TO SET THE BACK ANGLE.

5. Squeeze the bar off the floor and drag it up your legs in contact with your skin/sweats until it locks out at the top. If you have done the above sequence precisely as described, the bar will come off the ground in a perfectly vertical path. All the slack will have come out of the arms and hamstrings in step 4, the bar will not jerk off the ground, and your back will be in good extension. You will perceive that your hips are too high, but if you have completed step 4 correctly, the scapulas, bar, and mid-foot will be in vertical alignment and the pull will be perfect. The pull will seem "shorter" this way.

If you value your back operating correctly (or value your back not being operated upon) I would suggest not deadlifting with a rounded back until you can deadlift a fuckton without a rounded back. You'll probably need to deload significantly. That's okay.

For more specific form corrections, I'd post at the Starting Strength forums. They will almost certainly recommend that you buy the book Starting Strength. That is an excellent recommendation. They might be mean.

What a disgrace it is for a man to grow old without ever seeing the beauty and strength of which his body is capable. -Xenophon's Socrates

I was a competitive power lifter 20 plus years ago. Had a 600# gym DL and 570# meet DL done sumo style at 165 body Wt. Sumo is to hard on my hips now. I conventional DL and can get 400# for 4 reps. 185 body Wt.
Your form looked ok to me. Just do not round your back and think slow and controlled through out the lift. Injuries seem to happen when you go to fast. Also check out a web site called strong lifts 5x5, go to archives. This guy his some good vids.
Done right DLs can be amazing. I attribute me being able to grapple with younger and more skilled guys to deadlifting. Done Wrong you can really get hurt.